1. Technical Field
The disclosure generally relates to efficiency controlling modules and wireless communication devices using the same, particularly to efficiency controlling modules of a power amplifier and a wireless communication device using the same.
2. Description of Related Art
With developments in wireless communication and information processing technologies, wireless communication devices such as mobile phones and personal digital assistants (PDAs) are now in widespread use. Usually, a common wireless communication device includes a transceiver, a power amplifier, and a power source. The transceiver sends radio frequency (RF) signals to the power amplifier. The power amplifier amplifies the RF signals to insure the strength of the RF signals. The communication device communicates with other wireless communication devices or base station via the amplified radio frequency (RF) signals. The power source provides a working voltage to the power amplifier. However, the working voltage output from the power is commonly an invariable voltage, and cannot change according to the output efficiency of the transceiver. When the output efficiency of the transceiver is low, and the input voltage of the power amplifier is higher than the voltage which it actually needs, the efficiency of the power amplifier will be low.
Therefore, there is room for improvement within the art.